Coronary heart disease is one of the major health problems in indus trialized nations because of its high incidence and severity. Recent innovations in medical and surgical treatment of coronary heart dis ease have increased the importance of accurate diagnostic methods for determining the severity of coronary disease, identifying potential treatment alternatives, and evaluating the results of treatment. Great advances have also been made in basic research on coronary circula tion and its interaction with myocardial contraction and relaxation and neural and humoral control. With respect to...